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Other Subpopulations (other + subpopulation)
Selected AbstractsPedigree analysis in the Austrian Noriker draught horse: genetic diversity and the impact of breeding for coat colour on population structureJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 5 2009T. Druml Summary The pedigree of the current Austrian Noriker draught horse population comprising 2808 horses was traced back to the animals considered as founders of this breed. In total, the number of founders was 1991, the maximum pedigree length was 31 generations, with an average of 12.3 complete generations. Population structure in this autochthonous Austrian draught horse breed is defined by seven breeding regions (Carinthia, Lower Austria, Salzburg, Styria, Tyrol, Upper Austria and Vorarlberg) or through six coat colour groups (Bay, Black, Chestnut, Roan, Leopard, Tobiano). Average inbreeding coefficients within the breeding regions ranged from 4.5% to 5.5%; for the colour groups, the coefficients varied from 3.5% to 5.9%. Other measures of genetic variability like the effective number of founders, ancestors and founder genomes revealed a slightly different genetic background of the subpopulations. Average coancestries between and within breeding areas showed that the Salzburg population may be considered as the nucleus or original stock whereas all other subpopulations showed high relationship to horses from Salzburg. The target of draught horse breeding in the 21st century does not meet the breeding concept of maximizing genetic gains any more. Stabilizing selection takes place. In this study, we show that demographic factors as well as structure given by different coat colours helped to maintain genetic diversity in this endangered horse breed. [source] Fluctuating asymmetry as a bio-indicator in isolated populations of the Taita thrush: a Bayesian perspectiveJOURNAL OF BIOGEOGRAPHY, Issue 5-6 2002Luc Lens Aim We examined whether developmental instability can be used as a bio-monitoring tool in the endangered Taita thrush (Turdus helleri L.) through the measurement of individual levels of fluctuating asymmetry in tarsus length. Because estimates of the association between developmental instability, stress and fitness derived from traditional regression are biased, we compared parameter estimates obtained from likelihood based analysis with those obtained from a Bayesian latent variable model. Location Taita thrushes were captured and measured in three isolated cloud forest fragments located in the Taita Hills of south-east Kenya. Methods We applied mixed-effects regression with Restricted Maximum Likelihood parameter estimation (performed with SAS version 8.0) and Bayesian latent variable modelling (performed with WINBUGS version 1.3 and CODA version 0.4) to estimate unbiased levels of developmental instability and to model relationships between developmental instability and body condition in 312 Taita thrushes. Results Likelihood and Bayesian analyses yielded highly comparable results. Individual levels of developmental instability were strongly inversely related to body condition in the subpopulation with the lowest average condition. In contrast, both variables were unrelated in two other subpopulations with higher average condition. Such heterogeneity in association was in the direction expected by developmental theory, given that higher condition suggests more benign ambient conditions. The estimated levels of body condition in the three subpopulations did not support their presumed ranking in relation to environmental stress. Developmental instability and body condition are therefore believed to reflect different aspects of individual fitness. Main conclusions Variation in developmental homeostasis, either modelled as observable variable (fluctuating asymmetry) or latent variable (developmental instability), appears a useful indicator of stress effects in the Taita thrush. Because relationships between environmental stress and developmental instability may depend on the extent to which stress-mediated changes in other components of phenotypic variation are correlated, the study of trait asymmetry should preferably be combined with that of other measures of trait variability, such as trait size or organismal condition. [source] Personality Trait Profiles of Missionary AdolescentsJOURNAL OF TRAVEL MEDICINE, Issue 6 2000Terry L. Dwelle Background: The study objective was to compare the Taylor-Johnson Temperament Analysis secondary population norms for adolescents, to test results of Assemblies of God missionary adolescents, and determine if the mission's experience had significant impact on personality traits. Methods: A retrospective record review study of Taylor-Johnson Temperament Analysis test results administered to all missionary adolescents aged 13- to 18-years-old, having attended a yearly school of missions from 1986 to 1994, was performed. A two-sample, two-tailed t -test was used for statistical analysis. Test results were compared with standard adolescent and adult norms. Initial, and second test results when available, were compared for significant personality trait changes in adolescents over a 2,3 year interval, while in the mission's program. Subpopulation norms were calculated for the study group. Results: Initial tests from 438 study group adolescents demonstrated significant differences in 7 of 9 personality trait categories for males, and 8 of 9 for females, compared with test adolescent norms. Initial, and second test comparisons were performed in 67 adolescents, and showed no significant changes in the personality trait scores in males and females. Personality trait profiles for females more closely resembled adult than adolescent norms, with 8 of the 9 personality trait categories showing no significant difference between adult female norms and study females. Conclusions: Clinicians and mission's sending agencies should be aware of the unique Taylor-Johnson Temperament Analysis test patterns for missionary adolescents, and that Taylor-Johnson Temperament Analysis norm tables for adolescents seem inadequate in evaluating missionary adolescents. Appropriate subpopulation norms are likely necessary. The impact of missions on personality trait categories of missionary adolescents seems negligible, but needs further research with methods that assure follow-up testing. These considerations could apply to other subpopulations and psychological tests. [source] Using bald eagles to indicate the health of the Great Lakes' environmentLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 3 2002William W. Bowerman Abstract The bald eagle (Haliaeetus leucocephalus) is one of the most studied birds of North America, and a great amount of natural life-history information, including the response of various stressors on the eagles' ability to reproduce, are well known. In Michigan, the eagle has been chosen to track the trends of bioaccumulative compounds of concern across watersheds in the state. The state has been divided into major watersheds, and 20% of these are surveyed each year. A control area in northern Minnesota, Voyageurs National Park, is also sampled annually. We report here on the methods used, the preliminary results of the 1999 field season, and how differences in mercury concentrations varied over a 10-year period. Mercury in feathers of nestling eagles declined over time only in Lakes Michigan and Huron, but have not decreased among other subpopulations in Michigan. Concentrations of polychlorinated biphenyls (PCBs) and 4,4,-DDE in blood plasma from nestling eagles have declined over time for most subpopulations; however, they remain greater for breeding areas associated with the Great Lakes' food web. Sea eagles of the genus Haliaeetus are a good sentinel species to track trends in bioaccumulative compounds in aquatic systems. [source] | ||||||||||